<?php
/**
 * ownCloud - OC_Connector_Sabre_Sabre_CalDAV_Calendar
 *
 * @author Thomas Tanghus
 * @copyright 2012 Thomas Tanghus (thomas@tanghus.net)
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
 * License as published by the Free Software Foundation; either
 * version 3 of the License, or any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
 *
 * You should have received a copy of the GNU Affero General Public
 * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

/**
 * This class overrides Sabre_CalDAV_Calendar::getACL() to return read/write
 * permissions based on user and shared state and it overrides
 * Sabre_CalDAV_Calendar::getChild() and Sabre_CalDAV_Calendar::getChildren()
 * to instantiate OC_Connector_Sabre_CalDAV_CalendarObjects.
*/
class OC_Connector_Sabre_CalDAV_Calendar extends Sabre_CalDAV_Calendar {

   /**
   * Returns a list of ACE's for this node.
   *
   * Each ACE has the following properties:
   *   * 'privilege', a string such as {DAV:}read or {DAV:}write. These are
   *     currently the only supported privileges
   *   * 'principal', a url to the principal who owns the node
   *   * 'protected' (optional), indicating that this ACE is not allowed to
   *      be updated.
   *
   * @return array
   */
   public function getACL() {
      $calendar_model = new PCalendarModelCalendar();

      $readprincipal = $this->getOwner();
      $writeprincipal = $this->getOwner();
      $uid = $calendar_model->extractUserID($this->getOwner());

      if($uid != OC_USER::getUser()) {
         $sharedCalendar = OCP\Share::getItemSharedWithBySource('calendar', $this->calendarInfo['id']);
         if ($sharedCalendar && ($sharedCalendar['permissions'] & OCP\PERMISSION_READ)) {
            $readprincipal = 'principals/' . OC_USER::getUser();
         }
         if ($sharedCalendar && ($sharedCalendar['permissions'] & OCP\PERMISSION_UPDATE)) {
            $writeprincipal = 'principals/' . OC_USER::getUser();
         }
      }

      return array(
         array(
            'privilege' => '{DAV:}read',
            'principal' => $readprincipal,
            'protected' => true,
         ),
         array(
            'privilege' => '{DAV:}write',
            'principal' => $writeprincipal,
            'protected' => true,
         ),
         array(
            'privilege' => '{DAV:}read',
            'principal' => $readprincipal . '/calendar-proxy-write',
            'protected' => true,
         ),
         array(
            'privilege' => '{DAV:}write',
            'principal' => $writeprincipal . '/calendar-proxy-write',
            'protected' => true,
         ),
         array(
            'privilege' => '{DAV:}read',
            'principal' => $readprincipal . '/calendar-proxy-read',
            'protected' => true,
         ),
         array(
            'privilege' => '{' . Sabre_CalDAV_Plugin::NS_CALDAV . '}read-free-busy',
            'principal' => '{DAV:}authenticated',
            'protected' => true,
         ),

      );

   }

   /**
   * Returns a calendar object
   *
   * The contained calendar objects are for example Events or Todo's.
   *
   * @param string $name
   * @return Sabre_DAV_ICalendarObject
   */
   public function getChild($name) {

      $obj = $this->caldavBackend->getCalendarObject($this->calendarInfo['id'],$name);
      if (!$obj) throw new Sabre_DAV_Exception_NotFound('Calendar object not found');
      return new OC_Connector_Sabre_CalDAV_CalendarObject($this->caldavBackend,$this->calendarInfo,$obj);

   }

   /**
   * Returns the full list of calendar objects
   *
   * @return array
   */
   public function getChildren() {

      $objs = $this->caldavBackend->getCalendarObjects($this->calendarInfo['id']);
      $children = array();
      foreach($objs as $obj) {
         $children[] = new OC_Connector_Sabre_CalDAV_CalendarObject($this->caldavBackend,$this->calendarInfo,$obj);
      }
      return $children;

   }

}